Mule spindle



May 17, 1938. c. E. WILLIAMS ET AL MULE SPINDLE Filed Feb. 24, 1957 Ede/@607 Ceser 45 772%); Jrfid/Z747/Z9/JOPC Patented May 17, 1938 UNITED STATES PATENT OFFICE MULE SPINDLE ApplicationFebruaryM, 1937, Serial No. 127,434

4 Claims.

This invention relates to mules for spinning yarn and more particularly to the spindles used in such machines. Mule spindles are operated at the relatively high speed of 2000 to 4000 R. P. M. and the present tendency is toward still higher speeds and also toward longer bobbins and heavier yarn packages. This increase in speed and also in load produces a correspondingly increasing tendency toward vibration of the spindle whenever the load is unbalanced and the axis of the center of mass of the combined bobbin and yarn load fails to coincide with the axis of rotation.

It is the general object of our invention to provide an improved mule spindle, so constructed that vibration due to unbalanced load will be substantially eliminated.

To the attainment of this object, we provide a lower or step bearing fora mule spindle which is non-rigidly mounted and which permits a slight free transverse adjustment of the spindle to operating and load conditions.

A further object of our invention is to provide a construction by which installation and removal of spindles is facilitated.

Our invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claims.

30 A preferred form of the invention is shown in the drawing, in which Fig. l is a sectional side elevation of our improved spindle and its supporting structure;

Fig. 2 is a front elevation, partly in section, of the spindle base or stand;

Fig. 3 is an edge view of a bottom plate;

Fig. 4 is a plan view thereof;

Fig. 5 is a sectional side elevation of a bearing step;

Fig. 6 is a side elevation, partly in section, of the step bearing cap or cover; and

Fig. 7 is a side elevation, partly in section, of the upper spindle bushing.

Referring to the drawing, we have shown a 45 portion of the frame 10 of a mule carriage having a front board I I, top board l2, bottom board l4 and collar board l5, all of which parts are secured to the frame ID by screws l6.

Our improved mule spindle comprises a base or 5 stand adapted to be secured against a beveled under surface 2| of the collar board l5 by spaced binding screws 22. A spindle bushing 24 of fibre, bronze or other suitable material is forced into anopening 25 in the base 20 and projects upward therefrom, with the beveled upper portion of the bushing slidably fitting an inclined opening 26 in the collar board 15.

A spindle 30 is rotatably mounted in the spindle bushing 24 and at its lower end is provided with aninner ball race 32 which ooacts with an outer ball race 33 and a plurality of balls 34 to form an anti-friction bearing.

The outer race 33 is mounted in an enlarged recessed portion 35 of a spindle step 36. A shoulder 3'! forms an abutment for the race 33 when forced therein. The step 35 is furtherprovided witha central opening 38 and a recessed portion 39, through which lubricant may be supplied to the anti-friction bearing through any usual type of grease connection 40.

A dust cap or cover 42 fits snugly on a reduced portion '43 of the outer periphery of the cap 36. This dust cap or cover 42 is preferably formed from sheet metal and the construction thereof is clearly shown in Fig. 6.

The upper end of the dust cap 42 is so positioned that it just clears the under surface of the whirl 45 which is engaged by the usual spindle band B for driving the spindle.

The spindle base or stand 20 is provided with a lower portion mounted at the lower end of an offset connecting or gooseneck portion 5| and having a recess 52 therein. The recess 52 is slightly larger than the step 36, which fits somewhat freely therein. A bottom plate is secured to the under face of the base portion 50 by a plurality of screws 6|, and is provided with a central opening 32 to clear the grease connection 40.

A pair of pins 64 are fixed in the under side 01. the step 36 and extend downward through openings 65 in the plate 60 on which the step rests. The pins 64 are somewhat smaller than the openings 65 and have limited free play therein.

Having described the construction of our improved spindle, it will be noted that the spindle is a close running fit in the upper spindle bushing 24, but that the lower end of the spindle is rotatably mounted in a step bearing which is free to adjust itself radially of the spindle to a limited extent. This limited transverse free movement of the lower or step bearing permits the spindle to adjust its position to an unbalanced load and enables the spindle to run at relatively high speed and substantially without vibration even under unfavorable conditions.

This in itself is a very great advantage over the previous practice in mule spindles, but our construction has the further advantage that each spindle, spindle base and associated bearings forms a separate spindle unit which may be assembled and adjusted to satisfactory running condition before attachment to the mule carriage. Each spindle unit may also be separately removed from the carriage for repairs or adjustment.

Furthermore, when a spindle is to be thus re moved, the band B may be easily slipped over the lower end of the spindle base as soon as the base is loosened, thus greatly simplifying the removal and replacement of spindles as compared with the previous practice.

We also find it to be of great advantage to omit the separately supported upper and lower spindle bearings previously used and which required frequent and careful adjustment in order to keep the spindles running free. Moreover, a spindle rotating in two fixed spaced bearings was subject to extreme vibration under an unbalanced load, which vibration reduced the speed and resulted in uneven twist, loose winding at the nose of the bobbin, frequent yarn breakage and excessive wear.

Having thus described our invention and the advantages thereof, we do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what we claim is:--

1. In a mule having a carriage, in combination, a spindle having a driving whirl, a spindle stand, an upper spindle bearing fixed in said spindle stand, and a lower step bearing for said spindle, said upper bearing being a close running fit for said spindle above the spindle whirl and said step bearing being supported by said spindle stand but having limited free transverse movement relative thereto, and said spindle, stand and bearings comprising a self-contained unitary structure having a single point of attachment to said carriage at one end of said stand and said stand being separately removable from the mule carriage.

2. In a mule having a carriage with a collar board, in combination, a spindle having a driving whirl, a stand for said spindle supported by and depending from said collar board, a bearing bushing for said spindle mounted in the upper end of said stand and having a portion extending upward into an opening in said collar board, and a lower bearing for said spindle mounted in the lower part of said stand and having limited free transverse movement relative thereto.

3. In a mule having a carriage with a collar board, in combination, a spindle having a driving whirl, a stand for said spindle supported by and depending from said collar board, a bearing bushing for said spindle mounted in the upper end of said stand and having a portion extending upward into an opening in said collar board, and a lower bearing for said spindle mounted in the lower part of said stand and having limited free transverse movement relative thereto, the upper and lower portions of said stand being joined together by an offset connecting portion disposed entirely at the rear of said spindle.

4. In a mule having a carriage with a collar board, in combination, a spindle having a driving whirl, a spindle stand, an upper spindle bearing fixed in said spindle stand, and a lower step bearing for said spindle, said upper bearing being a close running fit for said spindle above the spindle whirl and said step bearing being supported by a depending portion of said spindle stand, and said spindle, stand and bearings comprising a self-contained unitary structure entirely supported by said collar board and free in its lower portions, said unitary structure being separately removable from said mule.

CHESTER E. WILLIAMS. I ARTHUR F. ANDERSON. 

